Characterizing the Three‐Dimensional Orientation in Polymers using FT‐IR Spectroscopy with Linear Polarized Light

The quantity of absorbance of linear polarized light depends for a given wavelength on the angle between an absorbing transition moment vector and the electric vector of the polarized light. Fraser used this relationship to interpret the infrared dichroism in axially oriented polymers. This model can be extended to calculate the orientation in three dimensions by transforming the Fraser's equation into a P₂‐Legendre polynomial. As a result the orientation in three directions—f_x, f_y, and f_z—can be calculated directly from the individual absorbances measured with an electric vector along the axes of interest, the structural absorbance A₀ of the sample, and the angle of the transition moment vector in reference to the chain axis. Applying the f values into ‘Hermans’ Orientation function', it becomes possible to calculate the average angle of the chain axis with reference to the axes of interest.

     

Alternating Copolymer of Sulfonated Poly(ether ether ketone‐benzimidazole)s (SPEEK‐BI) Bearing Acid and Base Moieties

A novel alternating copolymer of sulfonated poly(ether ether ketone‐benzimidazole)s (SPEEK‐BI) was synthesized by polycondensation of aromatic bisphenol containing benzimidazole and a mixture of sulfonated and non‐sulfonated difluorobenzophenones. By varying the amount of two difluorobenzophenones, the ratio of sulfonic acid unit to imidazole base was controlled straightforwardly. The polymer structure was characterized by ¹H NMR and IR spectroscopy. Two different methods of ion exchange capacity measurement supported a strong inter‐ and intra‐molecular interaction between acid and base units, which resulted in an improved mechanical strength as well as avoiding phase separation. Tough membranes with good mechanical stability in hot water (80 °C) and alcohol were obtained by solution casting, which is potential for applications in polymer electrolyte membrane fuel cells and membranes for separation of liquids or gases.

     

Diagnosis of pituitary abscess and treatment via transsphenoidal surgery: experience from 15 cases

ObjectivePituitary abscess is an often misdiagnosed, rare clinical disorder. To improve diagnostic accuracy and the efficacy of surgical and antibiotic therapy for patients with pituitary abscess, herein, we retrospectively reviewed 15 patients who presented with pituitary abscesses from 2005 to 2022.DesignRetrospective study.PatientsFifteen patients underwent transsphenoidal surgery and received antibiotic treatment.MeasurementsComplete details regarding medical history, clinical manifestations, laboratory examinations, imaging studies, and treatment strategies were obtained for all patients.ResultsMost patients presented with hypopituitarism and headaches, while some presented with fever, visual disturbances, and diabetes insipidus (DI). Abscesses showed significant annular enhancement post gadolinium injection. In most patients, pituitary abscess can be cured via microscopic or endoscopic drainage of the abscess followed by antibiotic treatment. Complete cure of pituitary abscess was observed in nine patients, with six cases of prolonged hypopituitarism and only one case of recurrence. Long-term hormone replacement therapy was effective in the postoperative management of hypopituitarism.ConclusionsThe typical manifestations of pituitary abscess include hypopituitarism and headaches; the presence of an enhanced ring at the edge of the mass on contrast-enhanced magnetic resonance images (MRI) is highly suggestive of pituitary abscess. We recommend antibiotic treatment for 4–6 weeks postoperatively, based on the results of bacterial cultures or metagenomic next-generation sequencing (mNGS).     

不同妊娠期孕妇甲状腺功能指标参考范围建立

目的:探讨不同妊娠期甲状腺功能指标参考范围,为本地区妊娠期甲状腺疾病提供可靠的诊断依据。方法:选择首次来本院进行甲状腺功能检测的不同妊娠期妇女为研究对象,分为妊娠早期(孕1~12周)、妊娠中期(孕13~27周)、妊娠晚期(孕28~40周),同期非妊娠妇女为对照组,各组220例,行促甲状腺激素(TSH)和游离甲状腺素(FT4)筛查。结果:检测中位数TSH分别为妊娠早期0.02~4.27mIU/L,妊娠中期0.08~5.07mIU/L,妊娠晚期期0.48~5.08mIU/L;FT4分别为妊娠早期12.08~24.80pmol/L,妊娠中期9.76~17.82pmol/L,妊娠晚期9.27~16.10pmol/L。与其他妊娠期及对照组比较,妊娠早期TSH水平最低,FT4最高(P<0.05)。结论:建立本地区不同妊娠期甲状腺功能指标参考值,有利于妊娠期甲状腺疾病的筛查及诊治。     

血清甲状腺激素对脑卒中事件的影响

目的通过分析急性脑卒中患者甲状腺激素水平的变化,探讨甲状腺激素与脑卒中事件的关系。方法选取2015年6月-2016年6月发病7 d内的急诊脑卒中患者164 例为急性脑卒中组,健康查体者180例为健康对照组。检测血三碘甲状腺原氨酸（T3）、甲状腺素（T4）、FT3 （游离T3）、FT4（游离T4）、促甲状腺素（TSH）、血清总胆固醇（TC）、三酰甘油（TG）、低密度脂蛋白（LDL）、高密度脂蛋白（HDL）、血糖、纤维蛋白原（FIB）及同型半胱氨酸的浓度。比较两组甲状腺激素水平的变化,分析甲状腺激素与脑卒中事件的关系。结果①急性脑卒中组FT4较健康对照组比较降低[（15.41±2.83）vs（16.78±3.74）, =0.027],FT3、T3、T4及TSH 与健康对照组比较差异无统计学意义（p >0.05）。②急性脑卒中组FIB、血糖、TC、LDL、载脂蛋白B及同型半胱氨酸（Hcy）较健康对照组升高（p <0.05）;HDL、载脂蛋白A 及三酰甘油在两组比较差异无统计学意义（p >0.05）。③Logistics回归分析提示FT4增高使脑卒中风险减低81.9%（1/OR）,高血糖和高Hcy 分别使脑卒中风险增加2.94 和1.07 倍（1/OR）。结论血清FT4减低可增加脑卒中事件发生的风险。     

脾肾阳虚型溃疡性结肠炎大鼠模型的建立

目的 初步研究并建立脾肾阳虚型溃疡性结肠炎大鼠模型。方法 通过灌服大黄水煎液、肌肉注射氢化可的松并结合TNBS（2, 4, 6-三硝基苯磺酸）混合乙醇灌肠建立脾肾阳虚型UC动物模型。将60只大鼠随机分为空白组、脾肾阳虚型UC模型7天、14天及21天组,采用酶联免疫法检测各组大鼠血清中FT3、FT4、T的含量。结果 与空白组比较,脾肾阳虚型UC模型7天、14天及21天组大鼠血清中FT3、FT4、T的含量均有程度的降低（P<0.05）;尤以模型21天组差异显著。结论 FT3、FT4、T是脾肾阳虚的敏感指标,检测血清FT3、FT4、T可以更好的佐证脾肾阳虚;证明了脾肾阳虚型UC动物模型复建成功。     

Intrinsic activity and comparative molecular dynamics of buspirone analogues at the 5-HT(1A) receptors

In CNS, the 5-hydroxytryptamine(1A) (5-HT(1A)) receptors exist in two different populations with different behavioural and physiological effects: (1) somatodendritic autoreceptors located pre-synaptically of 5-HT containing neurons and (2) receptors located post-synaptic to 5-HT containing neurons. Clinical studies have shown that 5-HT(1A) partial agonists have anxiolytic properties, while antagonists of pre-synaptical autoreceptors shorten the onset time of selective serotonin reuptake inhibitors (SSRIs). In the present study, the pre- and post-synaptic activity of structural analogues of buspirone was evaluated in animal models. A three dimensional model of the 5-HT(1A) receptor was used to study their interaction modes and helical displacements upon receptor binding. The predicted receptor-ligand interactions indicated similarities in the receptor binding modes for all buspirone analogues, and no clear relationship between receptor contact residues and activity at pre- and post-synaptic receptors. Comparative molecular dynamics (MD) simulations for 650ps indicated that pre-synaptic antagonistic behaviour is connected to large displacements of transmembrane helix (TMH) 7 upon binding, while pre-synaptic agonistic behaviour is connected to large displacements of TMH2 and small displacements of TMH7. Post-synaptic partial agonist behaviour is connected to large displacements of TMH4 and TMH5 upon binding, while post-synaptic antagonists only slightly displace these helices.     

Environmental lead exposure, maternal thyroid function, and childhood growth

Prenatal and early-life exposure to lead is hypothesized to have a range of adverse effects on childhood health. Drawing on data collected from a population-based prospective cohort study of a highly exposed town and a low exposed town in Kosovo, Yugoslavia we assessed whether elevated maternal blood lead (BPb) concentrations during pregnancy were associated with reduced childhood measures of attained height and BMI or growth rate, and whether the associations, if any, were mediated by maternal thyroid hormone concentration at mid-pregnancy. There was no association between blood lead levels and height or BMI in either town. However, increased maternal thyroid hormone was unexpectedly associated with reduced attained childhood height, and growth rate of height from 6.5 to 10 years, in the low-exposure town. We examine potential reasons for this unexpected inverse association.